Discrete sub-aortic stenosis and ventricular septal defect.

We present details of 15 children, aged 3 months to 11 years, with discrete sub-aortic stenosis and ventricular septal defect. We emphasise a high index of clinical suspicion and echocardiography as the best means of diagnosing this dangerous combination. Physical signs were those of ventricular septal defect in all patients, with auscultatory evidence of additional sub-aortic stenosis in only one. Five patients had a short early diastolic murmur of mild aortic incompetence. The electrocardiograph showed isolated left ventricular hypertrophy in eight patients. Cardiac catheterisation and angiography identified the ventricular septal defect in all cases but detected the sub-aortic stenosis in only eight. Cross sectional echocardiography showed both lesions in all 11 patients to whom it was available.